xref: /linux/drivers/iio/light/hid-sensor-prox.c (revision 7f71507851fc7764b36a3221839607d3a45c2025)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * HID Sensors Driver
4  * Copyright (c) 2014, Intel Corporation.
5  */
6 #include <linux/device.h>
7 #include <linux/platform_device.h>
8 #include <linux/module.h>
9 #include <linux/mod_devicetable.h>
10 #include <linux/slab.h>
11 #include <linux/hid-sensor-hub.h>
12 #include <linux/iio/iio.h>
13 #include <linux/iio/buffer.h>
14 #include "../common/hid-sensors/hid-sensor-trigger.h"
15 
16 static const u32 prox_usage_ids[] = {
17 	HID_USAGE_SENSOR_HUMAN_PRESENCE,
18 	HID_USAGE_SENSOR_HUMAN_PROXIMITY,
19 	HID_USAGE_SENSOR_HUMAN_ATTENTION,
20 };
21 
22 #define MAX_CHANNELS ARRAY_SIZE(prox_usage_ids)
23 
24 enum {
25 	HID_HUMAN_PRESENCE,
26 	HID_HUMAN_PROXIMITY,
27 	HID_HUMAN_ATTENTION,
28 };
29 
30 struct prox_state {
31 	struct hid_sensor_hub_callbacks callbacks;
32 	struct hid_sensor_common common_attributes;
33 	struct hid_sensor_hub_attribute_info prox_attr[MAX_CHANNELS];
34 	struct iio_chan_spec channels[MAX_CHANNELS];
35 	u32 channel2usage[MAX_CHANNELS];
36 	u32 human_presence[MAX_CHANNELS];
37 	int scale_pre_decml;
38 	int scale_post_decml;
39 	int scale_precision;
40 	unsigned long scan_mask[2]; /* One entry plus one terminator. */
41 	int num_channels;
42 };
43 
44 static const u32 prox_sensitivity_addresses[] = {
45 	HID_USAGE_SENSOR_HUMAN_PRESENCE,
46 	HID_USAGE_SENSOR_DATA_PRESENCE,
47 };
48 
49 #define PROX_CHANNEL(_is_proximity, _channel) \
50 	{\
51 		.type = _is_proximity ? IIO_PROXIMITY : IIO_ATTENTION,\
52 		.info_mask_separate = _is_proximity ? BIT(IIO_CHAN_INFO_RAW) :\
53 				      BIT(IIO_CHAN_INFO_PROCESSED),\
54 		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |\
55 		BIT(IIO_CHAN_INFO_SCALE) |\
56 		BIT(IIO_CHAN_INFO_SAMP_FREQ) |\
57 		BIT(IIO_CHAN_INFO_HYSTERESIS),\
58 		.indexed = _is_proximity,\
59 		.channel = _channel,\
60 	}
61 
62 /* Channel definitions (same order as prox_usage_ids) */
63 static const struct iio_chan_spec prox_channels[] = {
64 	PROX_CHANNEL(true, HID_HUMAN_PRESENCE),
65 	PROX_CHANNEL(true, HID_HUMAN_PROXIMITY),
66 	PROX_CHANNEL(false, 0),
67 };
68 
69 /* Adjust channel real bits based on report descriptor */
70 static void prox_adjust_channel_bit_mask(struct iio_chan_spec *channels,
71 					int channel, int size)
72 {
73 	channels[channel].scan_type.sign = 's';
74 	/* Real storage bits will change based on the report desc. */
75 	channels[channel].scan_type.realbits = size * 8;
76 	/* Maximum size of a sample to capture is u32 */
77 	channels[channel].scan_type.storagebits = sizeof(u32) * 8;
78 }
79 
80 /* Channel read_raw handler */
81 static int prox_read_raw(struct iio_dev *indio_dev,
82 			      struct iio_chan_spec const *chan,
83 			      int *val, int *val2,
84 			      long mask)
85 {
86 	struct prox_state *prox_state = iio_priv(indio_dev);
87 	struct hid_sensor_hub_device *hsdev;
88 	int report_id;
89 	u32 address;
90 	int ret_type;
91 	s32 min;
92 
93 	*val = 0;
94 	*val2 = 0;
95 	switch (mask) {
96 	case IIO_CHAN_INFO_RAW:
97 		if (chan->scan_index >= prox_state->num_channels)
98 			return -EINVAL;
99 		address = prox_state->channel2usage[chan->scan_index];
100 		report_id = prox_state->prox_attr[chan->scan_index].report_id;
101 		hsdev = prox_state->common_attributes.hsdev;
102 		min = prox_state->prox_attr[chan->scan_index].logical_minimum;
103 		hid_sensor_power_state(&prox_state->common_attributes, true);
104 		*val = sensor_hub_input_attr_get_raw_value(hsdev,
105 							   hsdev->usage,
106 							   address,
107 							   report_id,
108 							   SENSOR_HUB_SYNC,
109 							   min < 0);
110 		if (prox_state->channel2usage[chan->scan_index] ==
111 		    HID_USAGE_SENSOR_HUMAN_ATTENTION)
112 			*val *= 100;
113 		hid_sensor_power_state(&prox_state->common_attributes, false);
114 		ret_type = IIO_VAL_INT;
115 		break;
116 	case IIO_CHAN_INFO_SCALE:
117 		*val = prox_state->scale_pre_decml;
118 		*val2 = prox_state->scale_post_decml;
119 		ret_type = prox_state->scale_precision;
120 		break;
121 	case IIO_CHAN_INFO_OFFSET:
122 		*val = hid_sensor_convert_exponent(
123 			prox_state->prox_attr[chan->scan_index].unit_expo);
124 		ret_type = IIO_VAL_INT;
125 		break;
126 	case IIO_CHAN_INFO_SAMP_FREQ:
127 		ret_type = hid_sensor_read_samp_freq_value(
128 				&prox_state->common_attributes, val, val2);
129 		break;
130 	case IIO_CHAN_INFO_HYSTERESIS:
131 		ret_type = hid_sensor_read_raw_hyst_value(
132 				&prox_state->common_attributes, val, val2);
133 		break;
134 	default:
135 		ret_type = -EINVAL;
136 		break;
137 	}
138 
139 	return ret_type;
140 }
141 
142 /* Channel write_raw handler */
143 static int prox_write_raw(struct iio_dev *indio_dev,
144 			       struct iio_chan_spec const *chan,
145 			       int val,
146 			       int val2,
147 			       long mask)
148 {
149 	struct prox_state *prox_state = iio_priv(indio_dev);
150 	int ret = 0;
151 
152 	switch (mask) {
153 	case IIO_CHAN_INFO_SAMP_FREQ:
154 		ret = hid_sensor_write_samp_freq_value(
155 				&prox_state->common_attributes, val, val2);
156 		break;
157 	case IIO_CHAN_INFO_HYSTERESIS:
158 		ret = hid_sensor_write_raw_hyst_value(
159 				&prox_state->common_attributes, val, val2);
160 		break;
161 	default:
162 		ret = -EINVAL;
163 	}
164 
165 	return ret;
166 }
167 
168 static const struct iio_info prox_info = {
169 	.read_raw = &prox_read_raw,
170 	.write_raw = &prox_write_raw,
171 };
172 
173 /* Callback handler to send event after all samples are received and captured */
174 static int prox_proc_event(struct hid_sensor_hub_device *hsdev,
175 				unsigned usage_id,
176 				void *priv)
177 {
178 	struct iio_dev *indio_dev = platform_get_drvdata(priv);
179 	struct prox_state *prox_state = iio_priv(indio_dev);
180 
181 	dev_dbg(&indio_dev->dev, "prox_proc_event\n");
182 	if (atomic_read(&prox_state->common_attributes.data_ready)) {
183 		dev_dbg(&indio_dev->dev, "hid_sensor_push_data\n");
184 		iio_push_to_buffers(indio_dev, &prox_state->human_presence);
185 	}
186 
187 	return 0;
188 }
189 
190 /* Capture samples in local storage */
191 static int prox_capture_sample(struct hid_sensor_hub_device *hsdev,
192 				unsigned usage_id,
193 				size_t raw_len, char *raw_data,
194 				void *priv)
195 {
196 	struct iio_dev *indio_dev = platform_get_drvdata(priv);
197 	struct prox_state *prox_state = iio_priv(indio_dev);
198 	int multiplier = 1;
199 	int chan;
200 
201 	for (chan = 0; chan < prox_state->num_channels; chan++)
202 		if (prox_state->channel2usage[chan] == usage_id)
203 			break;
204 	if (chan == prox_state->num_channels)
205 		return -EINVAL;
206 
207 	if (usage_id == HID_USAGE_SENSOR_HUMAN_ATTENTION)
208 		multiplier = 100;
209 
210 	switch (raw_len) {
211 	case 1:
212 		prox_state->human_presence[chan] = *(u8 *)raw_data * multiplier;
213 		return 0;
214 	case 4:
215 		prox_state->human_presence[chan] = *(u32 *)raw_data * multiplier;
216 		return 0;
217 	}
218 
219 	return -EINVAL;
220 }
221 
222 /* Parse report which is specific to an usage id*/
223 static int prox_parse_report(struct platform_device *pdev,
224 				struct hid_sensor_hub_device *hsdev,
225 				struct prox_state *st)
226 {
227 	struct iio_chan_spec *channels = st->channels;
228 	int index = 0;
229 	int ret;
230 	int i;
231 
232 	for (i = 0; i < MAX_CHANNELS; i++) {
233 		u32 usage_id = prox_usage_ids[i];
234 
235 		ret = sensor_hub_input_get_attribute_info(hsdev,
236 							  HID_INPUT_REPORT,
237 							  hsdev->usage,
238 							  usage_id,
239 							  &st->prox_attr[index]);
240 		if (ret < 0)
241 			continue;
242 		st->channel2usage[index] = usage_id;
243 		st->scan_mask[0] |= BIT(index);
244 		channels[index] = prox_channels[i];
245 		channels[index].scan_index = index;
246 		prox_adjust_channel_bit_mask(channels, index,
247 					     st->prox_attr[index].size);
248 		dev_dbg(&pdev->dev, "prox %x:%x\n", st->prox_attr[index].index,
249 			st->prox_attr[index].report_id);
250 		index++;
251 	}
252 
253 	if (!index)
254 		return ret;
255 
256 	st->num_channels = index;
257 
258 	return 0;
259 }
260 
261 /* Function to initialize the processing for usage id */
262 static int hid_prox_probe(struct platform_device *pdev)
263 {
264 	struct hid_sensor_hub_device *hsdev = dev_get_platdata(&pdev->dev);
265 	int ret = 0;
266 	static const char *name = "prox";
267 	struct iio_dev *indio_dev;
268 	struct prox_state *prox_state;
269 
270 	indio_dev = devm_iio_device_alloc(&pdev->dev,
271 				sizeof(struct prox_state));
272 	if (!indio_dev)
273 		return -ENOMEM;
274 	platform_set_drvdata(pdev, indio_dev);
275 
276 	prox_state = iio_priv(indio_dev);
277 	prox_state->common_attributes.hsdev = hsdev;
278 	prox_state->common_attributes.pdev = pdev;
279 
280 	ret = hid_sensor_parse_common_attributes(hsdev, hsdev->usage,
281 					&prox_state->common_attributes,
282 					prox_sensitivity_addresses,
283 					ARRAY_SIZE(prox_sensitivity_addresses));
284 	if (ret) {
285 		dev_err(&pdev->dev, "failed to setup common attributes\n");
286 		return ret;
287 	}
288 
289 	ret = prox_parse_report(pdev, hsdev, prox_state);
290 	if (ret) {
291 		dev_err(&pdev->dev, "failed to setup attributes\n");
292 		return ret;
293 	}
294 
295 	indio_dev->num_channels = prox_state->num_channels;
296 	indio_dev->channels = prox_state->channels;
297 	indio_dev->available_scan_masks = prox_state->scan_mask;
298 	indio_dev->info = &prox_info;
299 	indio_dev->name = name;
300 	indio_dev->modes = INDIO_DIRECT_MODE;
301 
302 	atomic_set(&prox_state->common_attributes.data_ready, 0);
303 
304 	ret = hid_sensor_setup_trigger(indio_dev, name,
305 				&prox_state->common_attributes);
306 	if (ret) {
307 		dev_err(&pdev->dev, "trigger setup failed\n");
308 		return ret;
309 	}
310 
311 	ret = iio_device_register(indio_dev);
312 	if (ret) {
313 		dev_err(&pdev->dev, "device register failed\n");
314 		goto error_remove_trigger;
315 	}
316 
317 	prox_state->callbacks.send_event = prox_proc_event;
318 	prox_state->callbacks.capture_sample = prox_capture_sample;
319 	prox_state->callbacks.pdev = pdev;
320 	ret = sensor_hub_register_callback(hsdev, hsdev->usage,
321 					   &prox_state->callbacks);
322 	if (ret < 0) {
323 		dev_err(&pdev->dev, "callback reg failed\n");
324 		goto error_iio_unreg;
325 	}
326 
327 	return ret;
328 
329 error_iio_unreg:
330 	iio_device_unregister(indio_dev);
331 error_remove_trigger:
332 	hid_sensor_remove_trigger(indio_dev, &prox_state->common_attributes);
333 	return ret;
334 }
335 
336 /* Function to deinitialize the processing for usage id */
337 static void hid_prox_remove(struct platform_device *pdev)
338 {
339 	struct hid_sensor_hub_device *hsdev = dev_get_platdata(&pdev->dev);
340 	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
341 	struct prox_state *prox_state = iio_priv(indio_dev);
342 
343 	sensor_hub_remove_callback(hsdev, hsdev->usage);
344 	iio_device_unregister(indio_dev);
345 	hid_sensor_remove_trigger(indio_dev, &prox_state->common_attributes);
346 }
347 
348 static const struct platform_device_id hid_prox_ids[] = {
349 	{
350 		/* Format: HID-SENSOR-usage_id_in_hex_lowercase */
351 		.name = "HID-SENSOR-200011",
352 	},
353 	{
354 		/* Format: HID-SENSOR-tag-usage_id_in_hex_lowercase */
355 		.name = "HID-SENSOR-LISS-0226",
356 	},
357 	{ /* sentinel */ }
358 };
359 MODULE_DEVICE_TABLE(platform, hid_prox_ids);
360 
361 static struct platform_driver hid_prox_platform_driver = {
362 	.id_table = hid_prox_ids,
363 	.driver = {
364 		.name	= KBUILD_MODNAME,
365 		.pm	= &hid_sensor_pm_ops,
366 	},
367 	.probe		= hid_prox_probe,
368 	.remove		= hid_prox_remove,
369 };
370 module_platform_driver(hid_prox_platform_driver);
371 
372 MODULE_DESCRIPTION("HID Sensor Proximity");
373 MODULE_AUTHOR("Archana Patni <archana.patni@intel.com>");
374 MODULE_LICENSE("GPL");
375 MODULE_IMPORT_NS(IIO_HID);
376